Move org-news styles into a helper
Move executive offices out to their own view

The pages are going to be different enough that having its own view will
probably make life easier down the line. It will also make things easier
as the styling for the organisation show page isn't designed for
refactoring.
Style the executive office pages

First stab at the styling for executive office pages. I have moved the
dash-list style into a helper. It is currently duplicated in a couple of
places around the site and it will need those places updating to use the
helper.
Add tests for elements on organistion pages

Tried to split them as best I could I think these are all the tests
which should be shared between both executive offices and normal
organisations.
Add Promotional features for executive offices

Executive offices can have any number of "promotional features". Each
feature is made up of one or more "promotional feature items", which
consists of an image, some text, an optional title (with link) and up
to six additional links. Promotional feature items can be flagged as
being "double-width". These will be displayed with a larger image when
shown on frontend. The best way to understand this is probably by
checking out the visuals attached to the tracker story:
https://www.pivotaltracker.com/story/show/46261745
Add links for promotional feature items

These are managed using the standard nested attributes mechanism in
rails. I've based the JavaScript on that used for managing contact
phone numbers. It is slightly different here in that it uses the
built-in mechanism for removing nested associations by setting the
_destroy param, rather than massaging them in the controller.
DRY up attachment-related code in tests
FormBuilder renders horizontal layout checkboxes
Wire up promotional features to frontend.

Displays the promotional features according to the number and size
of the items within them. I'm not entirely happy with the use of the
instance variable to keep track of the column number, but I couldn't
think of a cleaner way to do this, given that the width of the items
can vary. Also: in an ideal world, there would be separate partials
for the single and double-width promo items, and we'd set a
to_partial_path method on the model to return the appropriate partial
path, but that is only available in Rails >= 3.2.
Update executive office header css selectors.

These class names need to match the slugs for Number 10 and the DPMO.
Remove unused model
Extract common pattern for file upload to Builder

By pulling the pattern for file uploads to the form builder, we can
DRY up a lot of the forms.
Move fixture file helper to one place

This helper can't simply go in test_helper.rb as that doesn't get
loaded by the cucumber tests. The factories.rb file seems like the
most sensible place for it.
DRY up promotional feature features
Only http(s) URLs are valid
Use the correct class names for records
Presenters simplify rendering of promo features

This moves the logic for displaying promotional features out of
helpers and view templates and into presenter objects.
Update feature step with new selector

To reflect the actual CSS used..
Use ActiveSupport goodies where possible
Merge pull request #429 from alphagov/promo-teasers

Promotional features for executive offices

https://www.pivotaltracker.com/story/show/46261745
https://www.pivotaltracker.com/story/show/47423821